Neutralizing apparatus



June 22, 1937. w. H. CHAPMAN NEUTRALIZING APPARATUS Filed March 3, 1957 Hz van Z01- IZCIzapzuan fiitarn iIli Patented June 22, 1937 UNITED ST'E'ES PATENT OFFIQE to Chapman Electric Neutralizer Company, Portland, Maine, a corporation of Maine Application March 3,

10 Claims.

" ing static electric charges.

In the type of apparatus with which my present invention is concerned, a plurality of discharge points as required by the Width of material to be treated are capacitatively connected to a source of high tension alternating current,

all of which discharge points are provided with a grounded conductor near them. In such apparatus, the active discharge points effect an ionizedatmosphere by which the static charges of the material under treatment are neutralized. As the discharge points are capacitatively connected to the source of alternating current, if there were no ground in operative proximity thereto, the static charge would collect and prevent the production of ions of the opposite polarity rendering the apparatus ineffective until the accumulated charge was allowed to escape.

The grounded conductor is, therefore, of real importance and attention is invited to certain of my patents in which different grounding means are shown. In my Letters Patent Nos. 1,653,599 and 1,841,323 I have shown the use of apparatus which includes an insulated conductor with which a plurality of discharge points are capacitatively coupled and which are held in desired relation to the conductor and to the grounded metallic tube. In my Letters Patent No. 1,787,188 I have shown a ground rod positioned parallel to and in working proximity to all the discharge points.

Attention is also invited to my Letters Patent No. 1,782,712 relating to the control of the static electric charges, as, for example, by reversing the polarity of the initial charge of the material in anticipation of the influence of a mechanical 45 factor which would impart a new charge of the same polarity as the original charge whereby neutralization at some point remote from the place available for the control apparatus is possible by varying the angular position of the 50 ground bar in relation to the discharge points. My present invention relates to an improved apparatus by which the static electricity may be efiectively controlled. Included in the advantages of my invention are its simplicity and 55 adaptability by the elimination of the rod type 1937, Serial No. 128,837

of ground conductor or the means holding each of said discharge points in working proximity to their grounded conductor so that novel neutralizing apparatus may be installed readily and grounded where desired. For example, certain types of printing presses make necessary the use of fingers, carrying the discharge points of sufficient length to reach past certain parts which prevent the location of a ground rod in proximity to their ends and necessitate the performance of the grounding function at some selected and accessible point.

In my invention, I utilize a metal tube containing the insulated cable, which tube carries a plurality of discharge points in contact therewith. The entire tube is served by a single ground discharge point located in proximity to the tube or by a single ground point in contact with the sleeve and in proximity to a grounded conductor or the discarge point and the grounded conductor may be located where desired away from the discharge tube so that the grounding of my apparatus may be efiected where convenient and desired. Preferably, the ground discharge point is adjustable relative to the tube or the grounded conductor to eiiect a complete neutralization or reversal of the polarity of the static electric charge.

In the accompanying drawing, I have illustrated preferred embodiments of my invention of which drawing:

Fig. 1 is an elevation partly broken away of a neutralizing apparatus in accordance with my invention.

Fig. 2 is an end view of Fig. 1.

Fig. 3 is a partly sectioned view of Fig. 1 along the lines 3--3.

Fig. 4 is a similar view of Fig. 1 along the lines 44, and

Fig. 5 is a similar view showing a modified form.

I have indicated at l supporting rods or arms which are connected to the machine (not shown) which for purposes of discussion may be considered as a press for printing the sheets.

I have indicated at 2 a terminal bushing of a moulded insulation, which bushing is provided with a terminal pin 3 comprising one part of a bayonet type socket for connection to a source of high tension alternating current. The bushing 2 is formed to receive one end of the heavily insulated cable 4 in contact with the terminal pin 3, the cable 4 being carried within the steel tube 5.

The other end of the cable i is threaded as at 6 to enter the threaded hard rubber head 1. The head I is formed to receive one end of the steel the fibre sleeve 8 on the tube 5 and c eve 3 overlying the bushing 2 and the sleeve 3% support its other end.

Fibre clamps H are utilized to support the asapparatus on the steel rods l which ay be locked in position by the set I shown a plurality of metal sleeves l2 loosely mounted on the tube Each of the slee s is formed with an internally threaded wnr. screws in; adapted to enter the interiorly threaded E8 of the rubber fingers i i and to conto .t the spring head E5 of the discharge points Thus, the rubber fingers id and M may be nod or loosened to permit their desired position on the tube relative to the moving Jets. The screws 2f! are provided with flattened surfaces 2% adapted to fit the slot in the tube I have shown a fibre member formed a apertu e shaped to fit the tube 5 and from itube the steel grounding point which threaded through the check nut 24 the fibre member 2i between which is posied the metal clip connection 24 to a ground iiiie this form of ground connection is pre i'erred for many uses, it will be appreciated that it is but illustrative of the required function of the grounds. As the metallic points it are capacitatively coupled to the source of alternating current, a ground of this type is essential and services the entire metal tube and accordingly each of the several discharge points l8.

It will be appreciated that the metal tube were directly grounded, it would be impossible to neutralize the static electric charge of the sheet S while if no ground were available, the would accumulate on the active discharge points 28 and prevent the production s of opposite polarity. By adjustment of the 1 nt relative to the tube 5 in accordance with re requirements of each situation, I am able to provide air across which a glow or corona discharge takes place thus effecting desired results. Thus, with the point 23 a certain distance in the tube 5, the material S will be perfectly neutralized, while with the point closer to the surfaces of the tube 5, the polarity of the charge of the sheet 8 may be reversed to limited degree whereby small subsequent charges will be completely neutralized.

In my invention, it is immaterial where the air gap is located. As described, it may be between steel tube 5 and the point 23. It may be between a point carried by the tube 5 and a ground member or the gap may be in the ground at a distance from the tube ii.

In accordance with my invention, the neutralization of the static electric charges of a moving sheet may be accurately controlled by my device which is not only simple in construction, but is also very readily installed even in those machines where the obstruction of certain parts has constituted a seriously troublesome factor.

What I therefore claim and desire to secure by Letters Patent is:

1. In apparatus for controlling the static electricity of a moving sheet, an insulated conductor for connection with a source of high tension altel-nating current, a metallic member capacitatively connected to said conductor, a plurality of discharge points carried by said member, and me ns to ground said member, and said means including an gap.

2. In apparatus for controlling the static electricity of a moving sheet, an insulated conductor for connection with a source of high tension alternating current, a metallic member capacitatively connected to said conductor, a plurality of discharge points carried by said member, means to ground said member, said means including an air gap, and means for varying the width of said gap.

3. In apparatus for controlling the static electricity of a moving sheet, an insulated conductor for connection with a source of high tension alternating current, a metallic member capacitatively connected to said conductor, a plurality of discharge points slidably carried by said member, means to ground said member, said means including an air gap, and means for varying the width of said gap.

4. In apparatus for controlling the static electricity of a moving sheet, an insulated conductor for connection with a source of high tension alternating current, a metallic member capacit-atively connected to said conductor, a plurality of discharge points loosely mounted on said member, and means to lock said discharge points in desired position on said member, means to ground said member, said means including an air gap, and means for varying the Width of said gap.

5. In apparatus for controlling the static electricity of a moving sheet, an insulated conductor for connection with a source of high tension alternating current, a plurality of interconnected discharge points capacitatively connected to said conductor, and ground means connected to all of said discharge points, said means including an air gap.

6. In apparatus for controlling the static electricity of a moving sheet, an insulated conductor for connection with a source of high tension alternating current, a plurality of interconnected discharge points capacitatively connected to said conductor, and ground means connected to all of said discharge points, said means including a ground discharge point and a member normally spaced therefrom effecting an air gap, and means for varying the width of said gap.

7. In apparatus for controlling the static electricity of a moving sheet, an insulated conductor for connection with a source of high tension alternating current, a metallic member capacitatively coupled to said conductor, a plurality of discharge points connected to said member and a ground, said ground including a ground discharge point and a non-conductive support on said member to hold said ground discharge point in desired relation to said member.

8. In apparatus for controlling the static electricity of a moving sheet, an insulated conductor for connection with a source of high tension alternating current, a metallic member capacitatively coupled to said conductor, a plurality of discharge points connected to said member, a ground, a non-conductive support on said member, a ground discharge point connected to said ground and mounted in air gap relation to said member in said support for adjustment relative to said member.

9. In apparatus for controlling the static electricity of a moving sheet, an insulated conductor for connection with a source of high tension alternating current, a metallic tube capacitatively connected to said conductor, a plurality of sleeves loosely carried by said tube, each of said sleeves including a hub, a finger for each sleeve having an aperture extending therethrough, a discharge point for each finger adapted to be carried by said finger within said aperture, each of said fingers and said hubs having interengaging threaded portions. effective to permit said finger to be threaded in said hub to bear against said tube to hold said sleeve in desired position, and said discharge point being formed to be held by said finger against said tube, and a ground, said ground including an adjustable ground discharge point spaced from said tube to ground the single polarity charge collected by all of said discharge points.

10. In apparatus for controlling the static electricity of a moving sheet, an insulated conductor for connection with a source of high tension alternating current, a metallic tube capacit-atively connected to said conductor, said tube having a longitudinal slot, a plurality of fingers, a plurality of screw members carried by said tube in said siot, each of said fingers having an aperture extending therethrough, a discharge point for each finger adapted to be carried by said finger Within said aperture, each of said fingers being threaded for engagement with one of said screws to permit said finger to be threaded to bear against said tube to hold said finger in desired position, and each of said discharge points being formed to be held by said finger in contact with said screw, and a ground, said ground including an adjustable ground discharge point spaced from said tube to ground the single polarity charge collected by all of said discharge points.

WILLIAM H. CHAPMAN. 

